Enabling IP carrier peering

ABSTRACT

Methods and systems may provide carrier ENUM based routing for subscriber devices (e.g., voice or other multimedia services over IP) to locate and to connect to subscriber devices of another IP peering carrier. A private ENUM database may be used to connect subscribers of disparate carriers using a domain for designated breakout gateway control functions.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of, and claims priority to, U.S.patent application Ser. No. 15/451,048, filed Mar. 6, 2017, entitled“Enabling IP Carrier Peering,” the entire contents of which are herebyincorporated herein by reference.

TECHNICAL FIELD

The technical field generally relates to providing communicationservices and, more specifically, to systems and methods for InternetProtocol (IP) connections between IP carriers.

BACKGROUND

A large number of connections between devices, such as telephone calls,are now being carried via packet-switched networks. IP networks haveevolved to allow users to send voice and data, including telephonecalls, through packet-switched networks, such as the Internet, insteadof through older networks like the PSTN. Accordingly, networks oftenutilize the Internet Protocol (IP), which is the basic transmissionprotocol used for Internet communications, to form these connections.For carriers to provide service to subscribers by using IP networks,however, it is necessary for networks to interconnect so that theirsubscribers can connect to each other.

Providing such interconnection generally involves a mechanism by whichcalls that are intended for disparate networks are sent through egressrouting nodes of one network to gateway nodes of other networks. To theextent that one of the available networks recognizes that thedestination device resides on it, the network will take steps to routethe call to the destination device.

A problem exists, however, in that neither the originating network northe recipient networks have insight into the eventual call path. Whenthe originating network detects initiation of call intended for a deviceon another network, it does not necessarily know the identity or therouting information of the recipient device. Accordingly, it must sendcall information to available networks and rely on the intendedrecipient network to take steps to complete the call. Similarly, therecipient network has no idea when or if a particular call initiated onanother network will be intended for it. Accordingly, it must “listen”for all calls initiated by all available networks to insure that it doesnot miss a call that may be intended for a subscriber. This approach iscostly because it expends system resources on the originating side bysending call requests to available networks regardless of whether allsuch networks are actually recipients and expends resources on therecipient side by requiring the monitoring of call requests by networksthat are not intended recipients. Therefore, what is needed is anapproach for efficient use of system resources while providing IPcarrier interconnection.

SUMMARY

Disclosed herein are methods and systems which provide carrier ENUMbased routing for subscriber devices (e.g., voice or other multimediaservices over IP) to locate and to connect to subscriber devices ofanother IP peering carrier. For example, a private ENUM may be used tomore efficiently connect subscribers of disparate carriers.

This Summary is provided to introduce a selection of concepts in asimplified form that are further described below in the DetailedDescription. This Summary is not intended to identify key features oressential features of the claimed subject matter, nor is it intended tobe used to limit the scope of the claimed subject matter. Furthermore,the claimed subject matter is not limited to limitations that solve anyor all disadvantages noted in any part of this disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

Reference will now be made to the accompanying drawings, which are notnecessarily drawn to scale.

FIG. 1 illustrates an exemplary system for implementing carrier ENUM.

FIG. 2A illustrates an exemplary flow diagram of processing an IP basedcall (e.g., VoLTE (voice over long term evolution)) from a firstsubscriber of a first carrier to a second subscriber of the firstcarrier or to a second subscriber of a second carrier;

FIG. 2B illustrates a continuation of flow in FIG. 2A of an exemplaryprocessing an IP based call from first subscriber of a first carrier tosecond subscriber of a second carrier;

FIG. 3 illustrates a schematic of an exemplary network device.

FIG. 4 illustrates an exemplary communication system that provideswireless telecommunication services over wireless communicationnetworks.

FIG. 5 illustrates an exemplary communication system that provideswireless telecommunication services over wireless communicationnetworks.

FIG. 6 illustrates an exemplary telecommunications system in which thedisclosed methods and processes may be implemented.

FIG. 7 illustrates an example system diagram of a radio access networkand a core network.

FIG. 8 depicts an overall block diagram of an example packet-basedmobile cellular network environment, such as a general packet radioservice (GPRS) network.

FIG. 9 illustrates an exemplary architecture of a GPRS network.

FIG. 10 is a block diagram of an exemplary public land mobile network(PLMN).

DETAILED DESCRIPTION

ENUM (tElephone NUmber Mapping) is a suite of protocols and architecturedesigned by the Internet Engineering task force to unify the E.164telephone numbering system with the IP addressing system. The presentdisclosure will not provide an in-depth description of the ENUMstandard, but will focus on the subject matter needed to describe theprinciples set forth herein. Nevertheless, an exemplary description ofENUM terminology, protocols, and infrastructure can be found in U.S.Pat. No. 8,792,481, entitled “Methods, systems, and computer programproducts for providing inter-carrier IP-based connections using a commontelephone number mapping architecture”, which is hereby incorporated byreference in its entirety.

One characteristic of ENUM is a hierarchy of databases that are used bynetworks to identify routing information to establish connectionsbetween the various devices that are residing thereon. A multiple-tiereddatabase structure is used to provide carriers with the ability to formconnections between various devices without necessarily sharing networkarchitecture and routing information.

Carriers using ENUM have access to an indirect lookup method to obtainNaming Authority Pointer Resource (NAPTR) records associated withvarious devices residing on other networks. A NAPTR record is receivedfrom a network-based Domain Name System (DNS) and is indexed on theE.164 telephone number of a device. A NAPTR record includes, among otherthings, information that designates how and where a device can becontacted. For example, a NAPTR record may designate what types ofcommunications a device can establish, such as a VoIP connection usingSession Initiation Protocol (SIP), a voice connection using the E.164telephone number, a short message service (SMS) or multimedia messageservice (MMS) session, etc. The NAPTR may provide a uniform resourceidentifier (URI) that identifies how to contact the terminal to use aselected service, and may designate a priority for each of the variousconnection methods. ENUM infrastructure includes a plurality of tiereddatabases that are utilized to locate subscriber devices on the variousnetworks making up the infrastructure. For the purposes of the presentdisclosure, one such database will now be described.

A private ENUM database generally provides routing information forsubscribers within a single network operated by a particularcommunication service provider. If a request is received from anoriginating device on a network to call a device having a particularnumber, the network will first check the private ENUM database. If thenumber resides in the private ENUM database, then the recipient devicealso resides on the network and the two devices may be connected. If theprivate ENUM database does not have a record for the number, then it isunderstood that the recipient device resides on an external carriernetwork or the recipient device does not belong to one of the IP endpoints of the same carrier (e.g., 3G or PSTN).

Disclosed herein are methods and systems which utilize a private ENUMdatabase that may enhance an originating network's ability to providecarrier ENUM based routing for subscribers (e.g., voice or othermultimedia services over IP) to locate and to connect to subscribers ofanother IP peering carrier. For example, a private ENUM may be used tomore efficiently connect subscribers of disparate carriers.

FIG. 1 illustrates an exemplary system that may enhance a carrier ENUMcapability via use of a private ENUM server. Device 101 (e.g., portabledigital assistants (PDAs), laptop computers, tablet devices and othermobile devices, such as cellular telephones, smart appliances, and soon) may attempt to connect to device 102 (e.g., mobile phone). Itassumed, in this scenario, that device 101 and device 102 (also referredherein as subscriber 101 and subscriber 102, respectively) are ondisparate carrier networks, a first carrier network and a second carriernetwork. At step 201, after originating processing is complete, callsare routed to terminating serving call session control function (S-CSCF)222 (e.g., an intra-network routing function). At step 202, S-CSCF 222initiates a private ENUM query to a private ENUM database 221 (alsoknown herein as private ENUM 221).

At step 203, private ENUM 221 matches a “foreign” destination number ornumber range and returns T1ENUM_1.firstnetwork.net domain, as anexample. Foreign in this context means a number or number range that isnot assigned to the first carrier's subscribers; it does not necessarilyrefer to an International number or number range. It is contemplatedherein that in addition to provisioning first carrier telephone numbersin the private ENUM, there is provisioning of other numbers (e.g., NPAs,international country codes, national number ranges, combinationsthereof, etc.) associated with the second carrier or multiple additionalcarriers, including carriers reached via 3^(rd) party hubbing carrierssuch as IP Exchange (IPX) carriers. The first carrier is provisioningnon-first carrier numbers in the private ENUM and having it return a newdomain(s) that may be used as criteria to direct the carrier ENUM query(e.g., step 208 discussed in more detail herein) to one of severalpossible Tier 0/1 ENUM providers. Furthermore, the returned domain(s)may be used as a means for the first carrier to direct the call tospecific subsets of network equipment which may provide optimizations incall routing, such as reducing call setup or media delay, providingspecific network functions (e.g., routing the call to equipment that isenabled to perform Carrier ENUM queries), reducing network costs, orother optimizations.

For additional perspective before referring to step 204, conventionallya private ENUM only contains subscriber telephone numbers of the firstcarrier. Since the destination of the call is to a telephone number (TN)owned by another carrier (second carrier), conventionally there is noprivate ENUM match and it just returns NXDOMAIN (non-existent domain).Conventionally, there is no query of a private DNS server or the like asdiscussed in more detail herein. Also, conventionally, without carrierENUM, 1) an S-CSCF would determine the call needs to route to the PSTN(via breakout gateway control function (BGCF)) due to receiving NXDOMIANfrom Private ENUM response; 2) S-CSCF sends call to a BGCF; and 3) BGCFroutes call to the PSTN.

With continued reference to FIG. 1, at step 204, S-CSCF 222 determinesT1ENUM_1.firstnetwork.net domain fully qualified domain name (FQDN) mapsto new bgcfpool1.firstnetwork.net FQDN. As discussed below this step maybe skipped. A fully qualified domain name (FQDN), sometimes alsoreferred to as an absolute domain name, is a domain name that specifiesits location in the tree hierarchy of the Domain Name System (DNS).Different S-CSCFs may map the common T1ENUM_1.firstnetwork.net todifferent bgcfpool<x>.firstnetwork.fqdns. At step 205, S-CSCF 222 sendsa query to DNS server 223 to resolve bgcfpool1.firstnetwork.net FQDN. Itis not required that S-CSCF 222 maps the receivedT1ENUM_1.firstnetwork.net domain to another FQDN (e.g.bgcfpool1.firstnetwork.net) prior to performing the DNS query at step204 and step 205. S-CSCF 222 may instead choose to resolve the receivedT1ENUM_1.firstnetwork.net domain.

The possible mapping of bgcfpool1.firstnetwork.net in step 204 and step205 may provide further flexibility in DNS resolution. For example,different S-CSCFs 222 may map bgcfpool1.firstnetwork.net to differentFQDNs, thereby choosing different BGCFs as the next hop. This may beuseful in reducing network delays allowing S-CSCFs to choose BGCFs thatare geographically local to each other.

At step 206, DNS server 223 resolves bgcfpool1.firstnetwork.net FQDNwith an IP address to a ENUM-enabled BGCF 224 (a subset of BGCFs offirst carrier), which is received by S-CSCF 222. The destinationtelephone numbers that the first carrier would initiate a Carrier ENUMquery for could be directed to a “subset” of the BGCFs in the network(there may be one or more BGCFs), which would limit the need to onlyequip a subset of BGCFs with the Carrier ENUM client capability. Callsfor the non-first carrier telephone numbers that may use ENUM may bedirected to a specific set of BGCFs 224. For additional perspective, itis significant to understand that conventionally when an S-CSCF receivesa call destined for an external network, (e.g., another carrier), theS-CSCF typically distributes the call among the BGCFs in the firstcarrier network (e.g., all the BGCFs). As such, all of the BGCFs in thenetwork would need to support the ability to initiate carrier ENUMqueries, even if the call did not require a carrier ENUM query. By usingthe bgcfpool1.firstnetwork.net (or T1ENUM_1.firstnetwork.net) FQDN forcalls that do require a carrier ENUM query, this allows the call to berouted to a limited set of ENUM-enabled BGCFs, thereby reducing thenumber of BGCFs that must be equipped to support carrier ENUM.

At step 207, S-CSCF 222 routes calls to the ENUM-enabled BGCFs 224(subset of BGCFs) based on DNS server 223 response of step 206. Callsthat do not require carrier ENUM, such as calls that returned anNXdomain at step 203 or at step 206, may be routed to those BGCFs 225that are not equipped with ENUM client. At step 208, carrier ENUM issupported, therefore BGCF 224 determines that a carrier ENUM queryshould be performed, such as to a Tier 0/1 ENUM server. Carrier ENUMclient of BGCF 224 (which may or may not be integrated with BGCF)initiates a query and receives a response, which may be to or from aTier 0/1 ENUM server. BGCF 224 may act like an ENUM client, therefore itmay query to Tier 0/1 ENUM provider database. The following is anexemplary query: ORIGIN 3.8.0.0.6.9.2.3.6.4.1.e164enum.net. At step 209,BGCF 224 routes call based upon carrier ENUM query response of step 208and other routing logic.

With continued reference to the scenario in FIG. 1, it should beunderstood that private ENUM 221 may match on foreign numbers (foreignin this context means not a home-network subscriber, not necessarilyInternational). Private ENUM 221 typically just contains home-networknumbers. A match on these non-home network destinations by private ENUM221 may indicate that a carrier ENUM query should be performed.Furthermore, unique domains may be provisioned for different foreignnumber ranges to be used as pointers to multiple Tier 0/1 ENUM servers.For example, Tier1ENUM1 may be used for calls to NumberRange1 (e.g., afirst number range) and Tier1ENUM2 for calls to NumberRange2 (a secondnumber range), etc. Step 204 may be skipped if T1ENUM_1.firstnetwork.netdomain provides information needed to route the call appropriately. Butas shown, at step 204, bgcfpool1.firstnetwork.net domain may be used tofurther control which BGCFs (e.g., carrier ENUM clients) should beselected by S-CSCF 222. For example, S-CSCF 222 may route to regionalBGCFs, based on the call's originating or terminating location. If step204 is not performed, the original T1ENUM_1.firstnetwork.net FQDN may beresolved in step 205 and step 206. It is contemplated herein thatT1ENUM_1.firstnetwork.net and the others are just exemplary domains andother domain that serve the same function may be used.

The Private ENUM mapping of foreign number ranges to unique FQDNs mayprovide multiple capabilities. A first capability allows for theindication of which destinations may use carrier ENUM to determine theterminating network. A second capability, is that because thedetermination of which destinations may use Carrier ENUM is made priorto the external network routing function that contains the carrier ENUMclient (e.g., BGCF), the intra-network routing function (e.g., S-CSCF)may now direct the calls that would initiate a carrier ENUM query tothose BGCFs enabled to perform the carrier ENUM query. This may allow anetwork provider to not have to equip all BGCFs to support a carrierENUM client. A third capability may be the use of different FQDNs withinthe private ENUM for different destination number ranges to choose amonga plurality of Tier 0/1 ENUM providers. For example, calls to a givencountry code may be routed to a subset of carrier ENUM clients (BGCFs)that are enabled to contact Tier 0/1 ENUM Provider #1, whereas calls toCountry Code #2 could be routed to a subset of carrier ENUM Clients(BGCFs) that are enabled to contact Tier 0/1 ENUM Provider #2.

It is contemplated herein that the disclosed subject matter, although inIMS terms (e.g., S-CSCF, BGCF) applies to other network architectures(e.g., it doesn't have to be IMS). S-CSCF 222 may be similar to ageneric intra-network routing function. As disclosed, S-CSCF 222 may bethe Private ENUM query and make routing decisions on which BGCF toselect. BGCFs 224 or BGCF 225 may be considered a generic, inter-network(i.e., external) routing function (the function determines how to bestroute a call to another network).

IPX eligible calls are calls that may be processed by the carrier ENUMenabled BGCFs to launch the InterCarrier Tier 0/1 ENUM query to the Tier0/1 ENUM vendor (IPX in this case). An IP exchange (IPX) network in oneexample is generally a network operated by a plurality of networkcarriers to provide for inter-network exchange of data between carriers.CC1 is one example of Tier 1. Other CC can also be Tier 1. For example,CC 44 (UK) is another example of Tier 1. A Tier 1 registry normallycovers all the numbers in a country. Tier 0 may include delegations toTier 1 registries based on country code . . . . As disclosed herein, itis not restricted to Tier 1 ENUM server, it may be Tier 0/1, if allother international carriers opt in to the Carrier ENUM of a carrier,for example.

FIG. 2A, illustrates an exemplary flow diagram of processing an IP basedcall (e.g., VoLTE (voice over long term evolution)) from a firstsubscriber of a first carrier to a second subscriber of the firstcarrier or to a second subscriber of a second carrier (FIG. A-FIG. 2B).At step 241, an IP call from first subscriber 101 of first carrier,intended for another subscriber of first carrier (not shown) or secondsubscriber 102 of second carrier, is received. The call (a request toconnect the first subscriber to another subscriber of first carrier orthe second subscriber) is received by S-CSCF 222 and sent to privateENUM 221. The request may include an e-164 request. At step 242, privateENUM 221 receives a first ENUM query with domain “e164.arpa.” At step243, private ENUM 221 determines which SIP URI (Session InitiationProtocol Uniform Resource Identifier), if any, is applicable for theENUM, which may be 10-digit number or appropriate variation thereof(e.g., country code) is stored within private ENUM 221. If an SIP URI ofhome.firstcarrier.net is retrieved (Yes), it indicates that the seconduser is also a subscriber to the first network. Therefore, in step 244,at S-CSCF 222 performs DNS look-up to resolve a domain name to IPaddress and completes the call (IP-to-IP) in step 245. However, if anSIP URI is not retrieved (No) or T1ENUM_1.firstnetwork.net is retrieved,it indicates that second subscriber 102 is not a subscriber to the firstcarrier network. In a first scenario T1ENUM_1.firstnetwork.net isretrieved and further processing is done as continued in flow A 250 ofFIG. 2B. In a second scenario, where there is no SIP URI retrieved thenthe call may be routed to BGCF for the PSTN to process.

FIG. 2B illustrates a continuation of flow in FIG. 2A of an exemplaryprocessing an IP based call from first subscriber 101 of a first carrierto second subscriber 102 of a second carrier. At step 243 of FIG. 2B,there is additional considerations by private ENUM 221. Private ENUM 221determines whether the ENUM has an entry for a number or number rangethat is not of the first carrier that corresponds to a domain (e.g.,T1ENUM_1.firstnetwork.net). If yes, then the process proceeds to step246. At step 246, DNS server 223 based on T1ENUM_1.firstnetwork.net (orsubsequent remapping to bgcfpool1.firstnetwork.net as disclosed above)provides the next hop FQDN that point to selected ENUM-enabled BGCFs 224(subset of BGCFs in first carrier network). At step 247, S-CSCF 222sends the traffic to a selected ENUM-enabled BGCFs 224. At step 248,BGCF 224 sends revised ENUM queries to Tier 1 ENUM server based on DNSserver 223 (which may be a private DNS server) record information ofTier 0/1 IP address. A Tier 0/1 ENUM server may provide name server (NS)records that provide routing information that is known to the Tier 0/1database, but is not known to a private ENUM database (or server). Forexample, a Tier 0/1 ENUM server may identify network databases of othernetworks, which are known to the Tier 0/1 ENUM servers along with rangesof numbers managed by these servers. These other servers are referred toas Tier 2 ENUM servers. Accordingly, a Tier 0/1 ENUM server may providethe name of a network and a Tier 2 ENUM server that manages a numberassociated with a particular device. The originating network may thencontact the appropriate Tier 2 ENUM server to receive information neededto complete a call. For further details with regard to this Tier 0/1ENUM server query (e.g., step 208), among other things, see U.S. patentapplication Ser. 15/222,337, entitled “Methods and Target Architecturefor Enabling IP Carrier Peering,” which is hereby incorporated byreference in its entirety.

With continued reference to FIG. 2B, if no at step 243, then at step 251the next hope FQDN points to the general pool of BGCFs, which may not beENUM enabled. At step 252, S-CSCF 222 sends the traffic to BGCFs. Atstep 253, the call may be routed to the PSTN or 2G or 3G network.

Disclosed herein are methods and systems to enable a private ENUM torespond to a telephone number of a different carrier. Conventionally,when detecting a non-carrier TN a private ENUM may abandon the call inan IP way and switch it to the PSTN. Also, conventionally ENUM wouldinclude the full telephone string. However, disclosed herein, a countrycode, a NPA (e.g., NPA 416), or subset of digits of the TN may be usedto direct calls to a subset of BGCFs, which may allow for more efficientprocessing of the call. For example, a call to a specific country code,or particular provider associated Country Code/National Number range isdetected, then the call may be routed to BGCFs that more efficientlyprocess calls destined to that country or number range. The componentsherein may be logical network components. For example, BGCFs may beconsidered a routing function for a call. In another example, functionsof the BGCF and S-CSCF may be integrated into one device or distributedacross multiple devices. Note that one possible advantage of reducingthe number of BGCFs that must be equipped to support carrier ENUM, isreducing costs that occur for having such functions enabled (e.g., costfor updating or maintaining software, licensing fees, etc.).

FIG. 3 is a block diagram of network device 300 that may be connected toor comprise a component of the network of FIG. 1. Network device 300 maycomprise hardware or a combination of hardware and software. Thefunctionality to facilitate telecommunications via a telecommunicationsnetwork may reside in one or combination of network devices 300. Networkdevice 300 depicted in FIG. 3 may represent or perform functionality ofan appropriate network device 300, or combination of network devices300, such as, for example, a component or various components of acellular broadcast system wireless network, a processor, a server, agateway, a node, a mobile switching center (MSC), a short messageservice center (SMSC), an automatic location function server (ALFS), agateway mobile location center (GMLC), a radio access network (RAN), aserving mobile location center (SMLC), or the like, or any appropriatecombination thereof. It is emphasized that the block diagram depicted inFIG. 3 is exemplary and not intended to imply a limitation to a specificimplementation or configuration. Thus, network device 300 may beimplemented in a single device or multiple devices (e.g., single serveror multiple servers, single gateway or multiple gateways, singlecontroller or multiple controllers). Multiple network entities may bedistributed or centrally located. Multiple network entities maycommunicate wirelessly, via hard wire, or any appropriate combinationthereof.

Network device 300 may comprise a processor 302 and a memory 304 coupledto processor 302. Memory 304 may contain executable instructions that,when executed by processor 302, cause processor 302 to effectuateoperations associated with mapping wireless signal strength. As evidentfrom the description herein, network device 300 is not to be construedas software per se.

In addition to processor 302 and memory 304, network device 300 mayinclude an input/output system 306. Processor 302, memory 304, andinput/output system 306 may be coupled together (coupling not shown inFIG. 3) to allow communications between them. Each portion of networkdevice 300 may comprise circuitry for performing functions associatedwith each respective portion. Thus, each portion may comprise hardware,or a combination of hardware and software. Accordingly, each portion ofnetwork device 300 is not to be construed as software per se.Input/output system 306 may be capable of receiving or providinginformation from or to a communications device or other network entitiesconfigured for telecommunications. For example input/output system 306may include a wireless communications (e.g., 3G/4G/GPS) card.Input/output system 306 may be capable of receiving or sending videoinformation, audio information, control information, image information,data, or any combination thereof. Input/output system 306 may be capableof transferring information with network device 300. In variousconfigurations, input/output system 306 may receive or provideinformation via any appropriate means, such as, for example, opticalmeans (e.g., infrared), electromagnetic means (e.g., RF, Wi-Fi,Bluetooth®, ZigBee®), acoustic means (e.g., speaker, microphone,ultrasonic receiver, ultrasonic transmitter), or a combination thereof.In an example configuration, input/output system 306 may comprise aWi-Fi finder, a two-way GPS chipset or equivalent, or the like, or acombination thereof.

Input/output system 306 of network device 300 also may contain acommunication connection 308 that allows network device 300 tocommunicate with other devices, network entities, or the like.Communication connection 308 may comprise communication media.Communication media typically embody computer-readable instructions,data structures, program modules or other data in a modulated datasignal such as a carrier wave or other transport mechanism and includesany information delivery media. By way of example, and not limitation,communication media may include wired media such as a wired network ordirect-wired connection, or wireless media such as acoustic, RF,infrared, or other wireless media. The term computer-readable media asused herein includes both storage media and communication media.Input/output system 306 also may include an input device 310 such askeyboard, mouse, pen, voice input device, or touch input device.Input/output system 306 may also include an output device 312, such as adisplay, speakers, or a printer.

Processor 302 may be capable of performing functions associated withtelecommunications, such as functions for processing broadcast messages,as described herein. For example, processor 302 may be capable of, inconjunction with any other portion of network device 300, determining atype of broadcast message and acting according to the broadcast messagetype or content, as described herein.

Memory 304 of network device 300 may comprise a storage medium having aconcrete, tangible, physical structure. As is known, a signal does nothave a concrete, tangible, physical structure. Memory 304, as well asany computer-readable storage medium described herein, is not to beconstrued as a signal. Memory 304, as well as any computer-readablestorage medium described herein, is not to be construed as a transientsignal. Memory 304, as well as any computer-readable storage mediumdescribed herein, is not to be construed as a propagating signal. Memory304, as well as any computer-readable storage medium described herein,is to be construed as an article of manufacture.

Memory 304 may store any information utilized in conjunction withtelecommunications. Depending upon the exact configuration or type ofprocessor, memory 304 may include a volatile storage 314 (such as sometypes of RAM), a nonvolatile storage 316 (such as ROM, flash memory), ora combination thereof. Memory 304 may include additional storage (e.g.,a removable storage 318 or a non-removable storage 320) including, forexample, tape, flash memory, smart cards, CD-ROM, DVD, or other opticalstorage, magnetic cassettes, magnetic tape, magnetic disk storage orother magnetic storage devices, USB-compatible memory, or any othermedium that can be used to store information and that can be accessed bynetwork device 300. Memory 304 may comprise executable instructionsthat, when executed by processor 302, cause processor 302 to effectuateoperations to map signal strengths in an area of interest.

FIG. 4 illustrates a functional block diagram depicting one example ofan LTE-EPS network architecture 400 related to the current disclosure.In particular, the network architecture 400 disclosed herein is referredto as a modified LTE-EPS architecture 400 to distinguish it from atraditional LTE-EPS architecture.

An example modified LTE-EPS architecture 400 is based at least in parton standards developed by the 3rd Generation Partnership Project (3GPP),with information available at www.3gpp.org. In one embodiment, theLTE-EPS network architecture 400 includes an access network 402, a corenetwork 404, e.g., an EPC or Common BackBone (CBB) and one or moreexternal networks 406, sometimes referred to as PDN or peer entities.Different external networks 406 can be distinguished from each other bya respective network identifier, e.g., a label according to DNS namingconventions describing an access point to the PDN. Such labels can bereferred to as Access Point Names (APN). External networks 406 caninclude one or more trusted and non-trusted external networks such as aninternet protocol (IP) network 408, an IP multimedia subsystem (IMS)network 410, and other networks 412, such as a service network, acorporate network, or the like.

Access network 402 can include an LTE network architecture sometimesreferred to as Evolved Universal mobile Telecommunication systemTerrestrial Radio Access (E UTRA) and evolved UMTS Terrestrial RadioAccess Network (E-UTRAN). Broadly, access network 402 can include one ormore communication devices, commonly referred to as UE 414, and one ormore wireless access nodes, or base stations 416 a, 416 b. Duringnetwork operations, at least one base station 416 communicates directlywith UE 414. Base station 416 can be an evolved Node B (eNB), with whichUE 414 communicates over the air and wirelessly. UEs 414 can include,without limitation, wireless devices, e.g., satellite communicationsystems, portable digital assistants (PDAs), laptop computers, tabletdevices and other mobile devices (e.g., cellular telephones, smartappliances, and so on). UEs 414 can connect to eNBs 416 when UE 414 iswithin range according to a corresponding wireless communicationtechnology.

UE 414 generally runs one or more applications that engage in a transferof packets between UE 414 and one or more external networks 406. Suchpacket transfers can include one of downlink packet transfers fromexternal network 406 to UE 414, uplink packet transfers from UE 414 toexternal network 406 or combinations of uplink and downlink packettransfers. Applications can include, without limitation, web browsing,VoIP, streaming media and the like. Each application can pose differentQuality of Service (QoS) requirements on a respective packet transfer.Different packet transfers can be served by different bearers withincore network 404, e.g., according to parameters, such as the QoS.

Core network 404 uses a concept of bearers, e.g., EPS bearers, to routepackets, e.g., IP traffic, between a particular gateway in core network404 and UE 414. A bearer refers generally to an IP packet flow with adefined QoS between the particular gateway and UE 414. Access network402, e.g., E UTRAN, and core network 404 together set up and releasebearers as required by the various applications. Bearers can beclassified in at least two different categories: (i) minimum guaranteedbit rate bearers, e.g., for applications, such as VoIP; and (ii)non-guaranteed bit rate bearers that do not require guarantee bit rate,e.g., for applications, such as web browsing.

In one embodiment, the core network 404 includes various networkentities, such as MME 418, SGW 420, Home Subscriber Server (HSS) 422,Policy and Charging Rules Function (PCRF) 424 and PGW 426. In oneembodiment, MME 418 comprises a control node performing a controlsignaling between various equipment and devices in access network 402and core network 404. The protocols running between UE 414 and corenetwork 404 are generally known as Non-Access Stratum (NAS) protocols.

For illustration purposes only, the terms MME 418, SGW 420, HSS 422 andPGW 426, and so on, can be server devices, but may be referred to in thesubject disclosure without the word “server.” It is also understood thatany form of such servers can operate in a device, system, component, orother form of centralized or distributed hardware and software. It isfurther noted that these terms and other terms such as bearer pathsand/or interfaces are terms that can include features, methodologies,and/or fields that may be described in whole or in part by standardsbodies such as the 3GPP. It is further noted that some or allembodiments of the subject disclosure may in whole or in part modify,supplement, or otherwise supersede final or proposed standards publishedand promulgated by 3GPP.

According to traditional implementations of LTE-EPS architectures, SGW420 routes and forwards all user data packets. SGW 420 also acts as amobility anchor for user plane operation during handovers between basestations, e.g., during a handover from first eNB 416 a to second eNB 416b as may be the result of UE 414 moving from one area of coverage, e.g.,cell, to another. SGW 420 can also terminate a downlink data path, e.g.,from external network 406 to UE 414 in an idle state, and trigger apaging operation when downlink data arrives for UE 414. SGW 420 can alsobe configured to manage and store a context for UE 414, e.g., includingone or more of parameters of the IP bearer service and network internalrouting information. In addition, SGW 420 can perform administrativefunctions, e.g., in a visited network, such as collecting informationfor charging (e.g., the volume of data sent to or received from theuser), and/or replicate user traffic, e.g., to support a lawfulinterception. SGW 420 also serves as the mobility anchor forinterworking with other 3GPP technologies such as universal mobiletelecommunication system (UMTS).

At any given time, UE 414 is generally in one of three different states:detached, idle, or active. The detached state is typically a transitorystate in which UE 414 is powered on but is engaged in a process ofsearching and registering with network 402. In the active state, UE 414is registered with access network 402 and has established a wirelessconnection, e.g., radio resource control (RRC) connection, with eNB 416.Whether UE 414 is in an active state can depend on the state of a packetdata session, and whether there is an active packet data session. In theidle state, UE 414 is generally in a power conservation state in whichUE 414 typically does not communicate packets. When UE 414 is idle, SGW420 can terminate a downlink data path, e.g., from one peer entity 406,and triggers paging of UE 414 when data arrives for UE 414. If UE 414responds to the page, SGW 420 can forward the IP packet to eNB 416 a.

HSS 422 can manage subscription-related information for a user of UE414. For example, HSS 422 can store information such as authorization ofthe user, security requirements for the user, quality of service (QoS)requirements for the user, etc. HSS 422 can also hold information aboutexternal networks 406 to which the user can connect, e.g., in the formof an APN of external networks 406. For example, MME 418 can communicatewith HSS 422 to determine if UE 414 is authorized to establish a call,e.g., a voice over IP (VoIP) call before the call is established.

PCRF 424 can perform QoS management functions and policy control. PCRF424 is responsible for policy control decision-making, as well as forcontrolling the flow-based charging functionalities in a policy controlenforcement function (PCEF), which resides in PGW 426. PCRF 424 providesthe QoS authorization, e.g., QoS class identifier and bit rates thatdecide how a certain data flow will be treated in the PCEF and ensuresthat this is in accordance with the user's subscription profile.

PGW 426 can provide connectivity between the UE 414 and one or more ofthe external networks 406. In illustrative network architecture 400, PGW426 can be responsible for IP address allocation for UE 414, as well asone or more of QoS enforcement and flow-based charging, e.g., accordingto rules from the PCRF 424. PGW 426 is also typically responsible forfiltering downlink user IP packets into the different QoS-based bearers.In at least some embodiments, such filtering can be performed based ontraffic flow templates. PGW 426 can also perform QoS enforcement, e.g.,for guaranteed bit rate bearers. PGW 426 also serves as a mobilityanchor for interworking with non-3GPP technologies such as CDMA2000.

Within access network 402 and core network 404 there may be variousbearer paths/interfaces, e.g., represented by solid lines 428 and 430.Some of the bearer paths can be referred to by a specific label. Forexample, solid line 428 can be considered an S1-U bearer and solid line432 can be considered an S5/S8 bearer according to LTE-EPS architecturestandards. Without limitation, reference to various interfaces, such asS1, X2, S5, S8, S11 refer to EPS interfaces. In some instances, suchinterface designations are combined with a suffix, e.g., a “U” or a “C”to signify whether the interface relates to a “User plane” or a “Controlplane.” In addition, the core network 404 can include various signalingbearer paths/interfaces, e.g., control plane paths/interfacesrepresented by dashed lines 430, 434, 436, and 438. Some of thesignaling bearer paths may be referred to by a specific label. Forexample, dashed line 430 can be considered as an S1-MME signalingbearer, dashed line 434 can be considered as an S11 signaling bearer anddashed line 436 can be considered as an S6a signaling bearer, e.g.,according to LTE-EPS architecture standards. The above bearer paths andsignaling bearer paths are only illustrated as examples and it should benoted that additional bearer paths and signaling bearer paths may existthat are not illustrated.

Also shown is a novel user plane path/interface, referred to as theS1-U+ interface 466. In the illustrative example, the S1-U+ user planeinterface extends between the eNB 416 a and PGW 426. Notably, S1-U+path/interface does not include SGW 420, a node that is otherwiseinstrumental in configuring and/or managing packet forwarding betweeneNB 416 a and one or more external networks 406 by way of PGW 426. Asdisclosed herein, the S1-U+ path/interface facilitates autonomouslearning of peer transport layer addresses by one or more of the networknodes to facilitate a self-configuring of the packet forwarding path. Inparticular, such self-configuring can be accomplished during handoversin most scenarios so as to reduce any extra signaling load on the S/PGWs420, 426 due to excessive handover events.

In some embodiments, PGW 426 is coupled to storage device 440, shown inphantom. Storage device 440 can be integral to one of the network nodes,such as PGW 426, for example, in the form of internal memory and/or diskdrive. It is understood that storage device 440 can include registerssuitable for storing address values. Alternatively or in addition,storage device 440 can be separate from PGW 426, for example, as anexternal hard drive, a flash drive, and/or network storage.

Storage device 440 selectively stores one or more values relevant to theforwarding of packet data. For example, storage device 440 can storeidentities and/or addresses of network entities, such as any of networknodes 418, 420, 422, 424, and 426, eNBs 416 and/or UE 414. In theillustrative example, storage device 440 includes a first storagelocation 442 and a second storage location 444. First storage location442 can be dedicated to storing a Currently Used Downlink address value442. Likewise, second storage location 444 can be dedicated to storing aDefault Downlink Forwarding address value 444. PGW 426 can read and/orwrite values into either of storage locations 442, 444, for example,managing Currently Used Downlink Forwarding address value 442 andDefault Downlink Forwarding address value 444 as disclosed herein.

In some embodiments, the Default Downlink Forwarding address for eachEPS bearer is the SGW S5-U address for each EPS Bearer. The CurrentlyUsed Downlink Forwarding address” for each EPS bearer in PGW 426 can beset every time when PGW 426 receives an uplink packet, e.g., a GTP-Uuplink packet, with a new source address for a corresponding EPS bearer.When UE 414 is in an idle state, the “Current Used Downlink Forwardingaddress” field for each EPS bearer of UE 414 can be set to a “null” orother suitable value.

In some embodiments, the Default Downlink Forwarding address is onlyupdated when PGW 426 receives a new SGW S5-U address in a predeterminedmessage or messages. For example, the Default Downlink Forwardingaddress is only updated when PGW 426 receives one of a Create SessionRequest, Modify Bearer Request and Create Bearer Response messages fromSGW 420.

As values 442, 444 can be maintained and otherwise manipulated on a perbearer basis, it is understood that the storage locations can take theform of tables, spreadsheets, lists, and/or other data structuresgenerally well understood and suitable for maintaining and/or otherwisemanipulate forwarding addresses on a per bearer basis.

It should be noted that access network 402 and core network 404 areillustrated in a simplified block diagram in FIG. 4. In other words,either or both of access network 402 and the core network 404 caninclude additional network elements that are not shown, such as variousrouters, switches and controllers. In addition, although FIG. 4illustrates only a single one of each of the various network elements,it should be noted that access network 402 and core network 404 caninclude any number of the various network elements. For example, corenetwork 404 can include a pool (i.e., more than one) of MMEs 418, SGWs420 or PGWs 426.

In the illustrative example, data traversing a network path between UE414, eNB 416 a, SGW 420, PGW 426 and external network 406 may beconsidered to constitute data transferred according to an end-to-end IPservice. However, for the present disclosure, to properly performestablishment management in LTE-EPS network architecture 400, the corenetwork, data bearer portion of the end-to-end IP service is analyzed.

An establishment may be defined herein as a connection set up requestbetween any two elements within LTE-EPS network architecture 400. Theconnection set up request may be for user data or for signaling. Afailed establishment may be defined as a connection set up request thatwas unsuccessful. A successful establishment may be defined as aconnection set up request that was successful.

In one embodiment, a data bearer portion comprises a first portion(e.g., a data radio bearer 446) between UE 414 and eNB 416 a, a secondportion (e.g., an S1 data bearer 428) between eNB 416 a and SGW 420, anda third portion (e.g., an S5/S8 bearer 432) between SGW 420 and PGW 426.Various signaling bearer portions are also illustrated in FIG. 4. Forexample, a first signaling portion (e.g., a signaling radio bearer 448)between UE 414 and eNB 416 a, and a second signaling portion (e.g., S1signaling bearer 430) between eNB 416 a and MME 418.

In at least some embodiments, the data bearer can include tunneling,e.g., IP tunneling, by which data packets can be forwarded in anencapsulated manner, between tunnel endpoints. Tunnels, or tunnelconnections can be identified in one or more nodes of network 400, e.g.,by one or more of tunnel endpoint identifiers, an IP address and a userdatagram protocol port number. Within a particular tunnel connection,payloads, e.g., packet data, which may or may not include protocolrelated information, are forwarded between tunnel endpoints.

An example of first tunnel solution 450 includes a first tunnel 452 abetween two tunnel endpoints 454 a and 456 a, and a second tunnel 452 bbetween two tunnel endpoints 454 b and 456 b. In the illustrativeexample, first tunnel 452 a is established between eNB 416 a and SGW420. Accordingly, first tunnel 452 a includes a first tunnel endpoint454 a corresponding to an S1-U address of eNB 416 a (referred to hereinas the eNB S1-U address), and second tunnel endpoint 456 a correspondingto an S1-U address of SGW 420 (referred to herein as the SGW S1-Uaddress). Likewise, second tunnel 452 b includes first tunnel endpoint454 b corresponding to an S5-U address of SGW 420 (referred to herein asthe SGW S5-U address), and second tunnel endpoint 456 b corresponding toan S5-U address of PGW 426 (referred to herein as the PGW S5-U address).

In at least some embodiments, first tunnel solution 450 is referred toas a two tunnel solution, e.g., according to the GPRS Tunneling ProtocolUser Plane (GTPv1-U based), as described in 3GPP specification TS29.281, incorporated herein in its entirety. It is understood that oneor more tunnels are permitted between each set of tunnel end points. Forexample, each subscriber can have one or more tunnels, e.g., one foreach PDP context that they have active, as well as possibly havingseparate tunnels for specific connections with different quality ofservice requirements, and so on.

An example of second tunnel solution 458 includes a single or directtunnel 460 between tunnel endpoints 462 and 464. In the illustrativeexample, direct tunnel 460 is established between eNB 416 a and PGW 426,without subjecting packet transfers to processing related to SGW 420.Accordingly, direct tunnel 460 includes first tunnel endpoint 462corresponding to the eNB S1-U address, and second tunnel endpoint 464corresponding to the PGW S5-U address. Packet data received at eitherend can be encapsulated into a payload and directed to the correspondingaddress of the other end of the tunnel. Such direct tunneling avoidsprocessing, e.g., by SGW 420 that would otherwise relay packets betweenthe same two endpoints, e.g., according to a protocol, such as the GTP-Uprotocol.

In some scenarios, direct tunneling solution 458 can forward user planedata packets between eNB 416 a and PGW 426, by way of SGW 420. That is,SGW 420 can serve a relay function, by relaying packets between twotunnel endpoints 416 a, 426. In other scenarios, direct tunnelingsolution 458 can forward user data packets between eNB 416 a and PGW426, by way of the S1 U+ interface, thereby bypassing SGW 420.

Generally, UE 414 can have one or more bearers at any one time. Thenumber and types of bearers can depend on applications, defaultrequirements, and so on. It is understood that the techniques disclosedherein, including the configuration, management and use of varioustunnel solutions 450, 458, can be applied to the bearers on anindividual bases. That is, if user data packets of one bearer, say abearer associated with a VoIP service of UE 414, then the forwarding ofall packets of that bearer are handled in a similar manner. Continuingwith this example, the same UE 414 can have another bearer associatedwith it through the same eNB 416 a. This other bearer, for example, canbe associated with a relatively low rate data session forwarding userdata packets through core network 404 simultaneously with the firstbearer. Likewise, the user data packets of the other bearer are alsohandled in a similar manner, without necessarily following a forwardingpath or solution of the first bearer. Thus, one of the bearers may beforwarded through direct tunnel 458; whereas, another one of the bearersmay be forwarded through a two-tunnel solution 450.

FIG. 5 depicts an exemplary diagrammatic representation of a machine inthe form of a computer system 500 within which a set of instructions,when executed, may cause the machine to perform any one or more of themethods described above. One or more instances of the machine canoperate, for example, as processor 302, device 101, DNS server 223,S-CSCF 222, MME 418, SGW 420, HSS 422, PCRF 424, PGW 426 and otherdevices of FIG. 1 and FIG. 4. In some embodiments, the machine may beconnected (e.g., using a network 502) to other machines. In a networkeddeployment, the machine may operate in the capacity of a server or aclient user machine in a server-client user network environment, or as apeer machine in a peer-to-peer (or distributed) network environment.

The machine may comprise a server computer, a client user computer, apersonal computer (PC), a tablet, a smart phone, a laptop computer, adesktop computer, a control system, a network router, switch or bridge,or any machine capable of executing a set of instructions (sequential orotherwise) that specify actions to be taken by that machine. It will beunderstood that a communication device of the subject disclosureincludes broadly any electronic device that provides voice, video ordata communication. Further, while a single machine is illustrated, theterm “machine” shall also be taken to include any collection of machinesthat individually or jointly execute a set (or multiple sets) ofinstructions to perform any one or more of the methods discussed herein.

Computer system 500 may include a processor (or controller) 504 (e.g., acentral processing unit (CPU)), a graphics processing unit (GPU, orboth), a main memory 506 and a static memory 508, which communicate witheach other via a bus 510. The computer system 500 may further include adisplay unit 512 (e.g., a liquid crystal display (LCD), a flat panel, ora solid state display). Computer system 500 may include an input device514 (e.g., a keyboard), a cursor control device 516 (e.g., a mouse), adisk drive unit 518, a signal generation device 520 (e.g., a speaker orremote control) and a network interface device 522. In distributedenvironments, the embodiments described in the subject disclosure can beadapted to utilize multiple display units 512 controlled by two or morecomputer systems 500. In this configuration, presentations described bythe subject disclosure may in part be shown in a first of display units512, while the remaining portion is presented in a second of displayunits 512.

The disk drive unit 518 may include a tangible computer-readable storagemedium 524 on which is stored one or more sets of instructions (e.g.,software 526) embodying any one or more of the methods or functionsdescribed herein, including those methods illustrated above.Instructions 526 may also reside, completely or at least partially,within main memory 506, static memory 508, or within processor 504during execution thereof by the computer system 500. Main memory 506 andprocessor 504 also may constitute tangible computer-readable storagemedia.

As shown in FIG. 6, telecommunication system 600 may include wirelesstransmit/receive units (WTRUs) 602, a RAN 604, a core network 606, apublic switched telephone network (PSTN) 608, the Internet 610, or othernetworks 612, though it will be appreciated that the disclosed examplescontemplate any number of WTRUs, base stations, networks, or networkelements. Each WTRU 602 may be any type of device configured to operateor communicate in a wireless environment. For example, a WTRU maycomprise, a device 101, network device 300, or the like, or anycombination thereof. By way of example, WTRUs 602 may be configured totransmit or receive wireless signals and may include a UE, a mobilestation, a fixed or mobile subscriber unit, a pager, a cellulartelephone, a PDA, a smartphone, a laptop, a netbook, a personalcomputer, a wireless sensor, consumer electronics, or the like. It isunderstood that the exemplary devices above may overlap in theirfunctionality and the terms are not necessarily mutually exclusive.WTRUs 602 may be configured to transmit or receive wireless signals overan air interface 614.

Telecommunication system 600 may also include one or more base stations616. Each of base stations 616 may be any type of device configured towirelessly interface with at least one of the WTRUs 602 to facilitateaccess to one or more communication networks, such as core network 606,PTSN 608, Internet 610, or other networks 612. By way of example, basestations 616 may be a base transceiver station (BTS), a Node-B, an eNodeB, a Home Node B, a Home eNode B, a site controller, an access point(AP), a wireless router, or the like. While base stations 616 are eachdepicted as a single element, it will be appreciated that base stations616 may include any number of interconnected base stations or networkelements.

RAN 604 may include one or more base stations 616, along with othernetwork elements (not shown), such as a base station controller (BSC), aradio network controller (RNC), or relay nodes. One or more basestations 616 may be configured to transmit or receive wireless signalswithin a particular geographic region, which may be referred to as acell (not shown). The cell may further be divided into cell sectors. Forexample, the cell associated with base station 616 may be divided intothree sectors such that base station 616 may include three transceivers:one for each sector of the cell. In another example, base station 616may employ multiple-input multiple-output (MIMO) technology and,therefore, may utilize multiple transceivers for each sector of thecell.

Base stations 616 may communicate with one or more of WTRUs 602 over airinterface 614, which may be any suitable wireless communication link(e.g., RF, microwave, infrared (IR), ultraviolet (UV), or visiblelight). Air interface 614 may be established using any suitable radioaccess technology (RAT).

More specifically, as noted above, telecommunication system 600 may be amultiple access system and may employ one or more channel accessschemes, such as CDMA, TDMA, FDMA, OFDMA, SC-FDMA, or the like. Forexample, base station 616 in RAN 604 and WTRUs 602 connected to RAN 604may implement a radio technology such as Universal MobileTelecommunications System (UMTS) Terrestrial Radio Access (UTRA) thatmay establish air interface 614 using wideband CDMA (WCDMA). WCDMA mayinclude communication protocols, such as High-Speed Packet Access (HSPA)or Evolved HSPA (HSPA+). HSPA may include High-Speed Downlink PacketAccess (HSDPA) or High-Speed Uplink Packet Access (HSUPA).

As another example base station 616 and WTRUs 602 that are connected toRAN 604 may implement a radio technology such as Evolved UMTSTerrestrial Radio Access (E-UTRA), which may establish air interface 614using LTE or LTE-Advanced (LTE-A).

Optionally base station 616 and WTRUs 602 connected to RAN 604 mayimplement radio technologies such as IEEE 602.16 (i.e., WorldwideInteroperability for Microwave Access (WiMAX)), CDMA2000, CDMA2000 1×,CDMA2000 EV-DO, Interim Standard 2000 (IS-2000), Interim Standard 95(IS-95), Interim Standard 856 (IS-856), GSM, Enhanced Data rates for GSMEvolution (EDGE), GSM EDGE (GERAN), or the like.

Base station 616 may be a wireless router, Home Node B, Home eNode B, oraccess point, for example, and may utilize any suitable RAT forfacilitating wireless connectivity in a localized area, such as a placeof business, a home, a vehicle, a campus, or the like. For example, basestation 616 and associated WTRUs 602 may implement a radio technologysuch as IEEE 602.11 to establish a wireless local area network (WLAN).As another example, base station 616 and associated WTRUs 602 mayimplement a radio technology such as IEEE 602.15 to establish a wirelesspersonal area network (WPAN). In yet another example, base station 616and associated WTRUs 602 may utilize a cellular-based RAT (e.g., WCDMA,CDMA2000, GSM, LTE, LTE-A, etc.) to establish a picocell or femtocell.As shown in FIG. 6, base station 616 may have a direct connection toInternet 610. Thus, base station 616 may not be required to accessInternet 610 via core network 606.

RAN 604 may be in communication with core network 606, which may be anytype of network configured to provide voice, data, applications, and/orvoice over internet protocol (VoIP) services to one or more WTRUs 602.For example, core network 606 may provide call control, billingservices, mobile location-based services, pre-paid calling, Internetconnectivity, video distribution or high-level security functions, suchas user authentication. Although not shown in FIG. 6, it will beappreciated that RAN 604 or core network 606 may be in direct orindirect communication with other RANs that employ the same RAT as RAN604 or a different RAT. For example, in addition to being connected toRAN 604, which may be utilizing an E-UTRA radio technology, core network606 may also be in communication with another RAN (not shown) employinga GSM radio technology.

Core network 606 may also serve as a gateway for WTRUs 602 to accessPSTN 608, Internet 610, or other networks 612. PSTN 608 may includecircuit-switched telephone networks that provide plain old telephoneservice (POTS). For LTE core networks, core network 606 may use IMS core614 to provide access to PSTN 608. Internet 610 may include a globalsystem of interconnected computer networks or devices that use commoncommunication protocols, such as the transmission control protocol(TCP), user datagram protocol (UDP), or IP in the TCP/IP internetprotocol suite. Other networks 612 may include wired or wirelesscommunications networks owned or operated by other service providers.For example, other networks 612 may include another core networkconnected to one or more RANs, which may employ the same RAT as RAN 604or a different RAT.

Some or all WTRUs 602 in telecommunication system 600 may includemulti-mode capabilities. That is, WTRUs 602 may include multipletransceivers for communicating with different wireless networks overdifferent wireless links. For example, one or more WTRUs 602 may beconfigured to communicate with base station 616, which may employ acellular-based radio technology, and with base station 616, which mayemploy an IEEE 802 radio technology.

FIG. 7 is an example system 400 including RAN 604 and core network 606.As noted above, RAN 604 may employ an E-UTRA radio technology tocommunicate with WTRUs 602 over air interface 614. RAN 604 may also bein communication with core network 606.

RAN 604 may include any number of eNBs 702 while remaining consistentwith the disclosed technology. One or more eNBs 702 may include one ormore transceivers for communicating with the WTRUs 602 over airinterface 614. Optionally, eNBs 702 may implement MIMO technology. Thus,one of eNBs 702, for example, may use multiple antennas to transmitwireless signals to, or receive wireless signals from, one of WTRUs 602.

Each of eNBs 702 may be associated with a particular cell (not shown)and may be configured to handle radio resource management decisions,handover decisions, scheduling of users in the uplink or downlink, orthe like. As shown in FIG. 7 eNBs 702 may communicate with one anotherover an X2 interface.

Core network 606, shown in FIG. 7, may include a mobility managementgateway or entity (MME) 704, a serving gateway 706, or a packet datanetwork (PDN) gateway 708. While each of the foregoing elements aredepicted as part of core network 606, it will be appreciated that anyone of these elements may be owned or operated by an entity other thanthe core network operator.

MME 704 may be connected to each of eNBs 702 in RAN 604 via an S1interface and may serve as a control node. For example, MME 704 may beresponsible for authenticating users of WTRUs 602, bearer activation ordeactivation, selecting a particular serving gateway during an initialattach of WTRUs 602, or the like. MME 704 may also provide a controlplane function for switching between RAN 604 and other RANs (not shown)that employ other radio technologies, such as GSM or WCDMA.

Serving gateway 706 may be connected to each of eNBs 702 in RAN 604 viathe S1 interface. Serving gateway 706 may generally route or forwarduser data packets to or from the WTRUs 602. Serving gateway 706 may alsoperform other functions, such as anchoring user planes duringinter-eNode B handovers, triggering paging when downlink data isavailable for WTRUs 602, managing or storing contexts of WTRUs 602, orthe like.

Serving gateway 706 may also be connected to PDN gateway 708, which mayprovide WTRUs 602 with access to packet-switched networks, such asInternet 610, to facilitate communications between WTRUs 602 andIP-enabled devices.

Core network 606 may facilitate communications with other networks. Forexample, core network 606 may provide WTRUs 602 with access tocircuit-switched networks, such as PSTN 608, such as through IMS core614, to facilitate communications between WTRUs 602 and traditionalland-line communications devices. In addition, core network 606 mayprovide the WTRUs 602 with access to other networks 612, which mayinclude other wired or wireless networks that are owned or operated byother service providers.

FIG. 8 depicts an overall block diagram of an example packet-basedmobile cellular network environment, such as a GPRS network as describedherein. In the example packet-based mobile cellular network environmentshown in FIG. 8, there are a plurality of base station subsystems (BSS)800 (only one is shown), each of which comprises a base stationcontroller (BSC) 802 serving a plurality of BTSs, such as BTSs 804, 806,808. BTSs 804, 806, 808 are the access points where users ofpacket-based mobile devices become connected to the wireless network. Inexample fashion, the packet traffic originating from mobile devices istransported via an over-the-air interface to BTS 808, and from BTS 808to BSC 802. Base station subsystems, such as BSS 800, are a part ofinternal frame relay network 810 that can include a service GPRS supportnodes (SGSN), such as SGSN 812 or SGSN 814. Each SGSN 812, 814 isconnected to an internal packet network 816 through which SGSN 812, 814can route data packets to or from a plurality of gateway GPRS supportnodes (GGSN) 818, 820, 822. As illustrated, SGSN 814 and GGSNs 818, 820,822 are part of internal packet network 816. GGSNs 818, 820, 822 mainlyprovide an interface to external IP networks such as PLMN 824, corporateintranets/internets 826, or Fixed-End System (FES) or the publicInternet 828. As illustrated, subscriber corporate network 826 may beconnected to GGSN 820 via a firewall 830. PLMN 824 may be connected toGGSN 820 via a boarder gateway router (BGR) 832. A Remote AuthenticationDial-In User Service (RADIUS) server 834 may be used for callerauthentication when a user calls corporate network 826.

Generally, there may be a several cell sizes in a network, referred toas macro, micro, pico, femto or umbrella cells. The coverage area ofeach cell is different in different environments. Macro cells can beregarded as cells in which the base station antenna is installed in amast or a building above average roof top level. Micro cells are cellswhose antenna height is under average roof top level. Micro cells aretypically used in urban areas. Pico cells are small cells having adiameter of a few dozen meters. Pico cells are used mainly indoors.Femto cells have the same size as pico cells, but a smaller transportcapacity. Femto cells are used indoors, in residential or small businessenvironments. On the other hand, umbrella cells are used to covershadowed regions of smaller cells and fill in gaps in coverage betweenthose cells.

FIG. 9 illustrates an exemplary architecture of a typical GPRS network900 as described herein. The architecture depicted in FIG. 9 may besegmented into four groups: users 902, RAN 904, core network 906, andinterconnect network 908. Users 902 comprise a plurality of end users,who each may use one or more devices 910. Note that device 910 isreferred to as a mobile subscriber (MS) in the description of networkshown in FIG. 9. In an example, device 910 comprises a communicationsdevice (e.g., device 102, S-CSCF 222, network device 300, any ofdetected devices 500, second device 508, access device 604, accessdevice 606, access device 608, access device 610 or the like, or anycombination thereof). Radio access network 904 comprises a plurality ofBSSs such as BSS 912, which includes a BTS 914 and a BSC 916. Corenetwork 906 may include a host of various network elements. Asillustrated in FIG. 9, core network 906 may comprise MSC 918, servicecontrol point (SCP) 920, gateway MSC (GMSC) 922, SGSN 924, home locationregister (HLR) 926, authentication center (AuC) 928, domain name system(DNS) server 930, and GGSN 932. Interconnect network 908 may alsocomprise a host of various networks or other network elements. Asillustrated in FIG. 9, interconnect network 908 comprises a PSTN 934, anFES/Internet 936, a firewall 1038, or a corporate network 940.

An MSC can be connected to a large number of BSCs. At MSC 918, forinstance, depending on the type of traffic, the traffic may be separatedin that voice may be sent to PSTN 934 through GMSC 922, or data may besent to SGSN 924, which then sends the data traffic to GGSN 932 forfurther forwarding.

When MSC 918 receives call traffic, for example, from BSC 916, it sendsa query to a database hosted by SCP 920, which processes the request andissues a response to MSC 918 so that it may continue call processing asappropriate.

HLR 926 is a centralized database for users to register to the GPRSnetwork. HLR 926 stores static information about the subscribers such asthe International Mobile Subscriber Identity (IMSI), subscribedservices, or a key for authenticating the subscriber. HLR 926 alsostores dynamic subscriber information such as the current location ofthe MS. Associated with HLR 926 is AuC 928, which is a database thatcontains the algorithms for authenticating subscribers and includes theassociated keys for encryption to safeguard the user input forauthentication.

In the following, depending on context, “mobile subscriber” or “MS”sometimes refers to the end user and sometimes to the actual portabledevice, such as a mobile device, used by an end user of the mobilecellular service. When a mobile subscriber turns on his or her mobiledevice, the mobile device goes through an attach process by which themobile device attaches to an SGSN of the GPRS network. In FIG. 9, whenMS 910 initiates the attach process by turning on the networkcapabilities of the mobile device, an attach request is sent by MS 910to SGSN 924. The SGSN 924 queries another SGSN, to which MS 910 wasattached before, for the identity of MS 910. Upon receiving the identityof MS 910 from the other SGSN, SGSN 924 requests more information fromMS 910. This information is used to authenticate MS 910 together withthe information provided by HLR 926. Once verified, SGSN 924 sends alocation update to HLR 926 indicating the change of location to a newSGSN, in this case SGSN 924. HLR 926 notifies the old SGSN, to which MS910 was attached before, to cancel the location process for MS 910. HLR926 then notifies SGSN 924 that the location update has been performed.At this time, SGSN 924 sends an Attach Accept message to MS 910, whichin turn sends an Attach Complete message to SGSN 924.

Next, MS 910 establishes a user session with the destination network,corporate network 940, by going through a Packet Data Protocol (PDP)activation process. Briefly, in the process, MS 910 requests access tothe Access Point Name (APN), for example, UPS.com, and SGSN 924 receivesthe activation request from MS 910. SGSN 924 then initiates a DNS queryto learn which GGSN 932 has access to the UPS.com APN. The DNS query issent to a DNS server within core network 906, such as DNS server 930,which is provisioned to map to one or more GGSNs in core network 906.Based on the APN, the mapped GGSN 932 can access requested corporatenetwork 940. SGSN 924 then sends to GGSN 932 a Create PDP ContextRequest message that contains necessary information. GGSN 932 sends aCreate PDP Context Response message to SGSN 924, which then sends anActivate PDP Context Accept message to MS 910.

Once activated, data packets of the call made by MS 910 can then gothrough RAN 904, core network 906, and interconnect network 908, in aparticular FES/Internet 936 and firewall 1038, to reach corporatenetwork 940.

FIG. 10 illustrates a PLMN block diagram view of an exemplaryarchitecture of a telecommunications system that may be used by IPpeering system disclosed herein. In FIG. 10, solid lines may representuser traffic signals, and dashed lines may represent support signaling.MS 1002 is the physical equipment used by the PLMN subscriber. Forexample, device 101, network device 300, the like, or any combinationthereof may serve as MS 1002. MS 1002 may be one of, but not limited to,a cellular telephone, a cellular telephone in combination with anotherelectronic device or any other wireless mobile communication device.

MS 1002 may communicate wirelessly with BSS 1004. BSS 1004 contains BSC1006 and a BTS 1008. BSS 1004 may include a single BSC 1006/BTS 1008pair (base station) or a system of BSC/BTS pairs that are part of alarger network. BSS 1004 is responsible for communicating with MS 1002and may support one or more cells. BSS 1004 is responsible for handlingcellular traffic and signaling between MS 1002 and a core network 1010.Typically, BSS 1004 performs functions that include, but are not limitedto, digital conversion of speech channels, allocation of channels tomobile devices, paging, or transmission/reception of cellular signals.

Additionally, MS 1002 may communicate wirelessly with RNS 1012. RNS 1012contains a Radio Network Controller (RNC) 1014 and one or more Nodes B1016. RNS 1012 may support one or more cells. RNS 1012 may also includeone or more RNC 1014/Node B 1016 pairs or alternatively a single RNC1014 may manage multiple Nodes B 1016. RNS 1012 is responsible forcommunicating with MS 1002 in its geographically defined area. RNC 1014is responsible for controlling Nodes B 1016 that are connected to it andis a control element in a UMTS radio access network. RNC 1014 performsfunctions such as, but not limited to, load control, packet scheduling,handover control, security functions, or controlling MS 1002 access tocore network 1010.

An E-UTRA Network (E-UTRAN) 1018 is a RAN that provides wireless datacommunications for MS 1002 and UE 1024. E-UTRAN 1018 provides higherdata rates than traditional UMTS. It is part of the LTE upgrade formobile networks, and later releases meet the requirements of theInternational Mobile Telecommunications (IMT) Advanced and are commonlyknown as a 4G networks. E-UTRAN 1018 may include of series of logicalnetwork components such as E-UTRAN Node B (eNB) 1020 and E-UTRAN Node B(eNB) 1022. E-UTRAN 1018 may contain one or more eNBs. User equipment(UE) 1024 may be any mobile device capable of connecting to E-UTRAN 1018including, but not limited to, a personal computer, laptop, mobilephone, wireless router, or other device capable of wireless connectivityto E-UTRAN 1018. The improved performance of the E-UTRAN 1018 relativeto a typical UMTS network allows for increased bandwidth, spectralefficiency, and functionality including, but not limited to, voice,high-speed applications, large data transfer or IPTV, while stillallowing for full mobility.

Typically MS 1002 may communicate with any or all of BSS 1004, RNS 1012,or E-UTRAN 1018. In a illustrative system, each of BSS 1004, RNS 1012,and E-UTRAN 1018 may provide MS 1002 with access to core network 1010.Core network 1010 may include of a series of devices that route data andcommunications between end users. Core network 1010 may provide networkservice functions to users in the circuit switched (CS) domain or thepacket switched (PS) domain. The CS domain refers to connections inwhich dedicated network resources are allocated at the time ofconnection establishment and then released when the connection isterminated. The PS domain refers to communications and data transfersthat make use of autonomous groupings of bits called packets. Eachpacket may be routed, manipulated, processed or handled independently ofall other packets in the PS domain and does not require dedicatednetwork resources.

The circuit-switched MGW function (CS-MGW) 1026 is part of core network1010, and interacts with VLR/MSC server 1028 and GMSC server 1030 inorder to facilitate core network 1010 resource control in the CS domain.Functions of CS-MGW 1026 include, but are not limited to, mediaconversion, bearer control, payload processing or other mobile networkprocessing such as handover or anchoring. CS-MGW 1026 may receiveconnections to MS 1002 through BSS 1004 or RNS 1012.

SGSN 1032 stores subscriber data regarding MS 1002 in order tofacilitate network functionality. SGSN 1032 may store subscriptioninformation such as, but not limited to, the IMSI, temporary identities,or PDP addresses. SGSN 1032 may also store location information such as,but not limited to, GGSN address for each GGSN 1034 where an active PDPexists. GGSN 1034 may implement a location register function to storesubscriber data it receives from SGSN 1032 such as subscription orlocation information.

Serving gateway (S-GW) 1036 is an interface which provides connectivitybetween E-UTRAN 1018 and core network 1010. Functions of S-GW 1036include, but are not limited to, packet routing, packet forwarding,transport level packet processing, or user plane mobility anchoring forinter-network mobility. PCRF 1038 uses information gathered from P-GW1036, as well as other sources, to make applicable policy and chargingdecisions related to data flows, network resources or other networkadministration functions. PDN gateway (PDN-GW) 1040 may provideuser-to-services connectivity functionality including, but not limitedto, GPRS/EPC network anchoring, bearer session anchoring and control, orIP address allocation for PS domain connections.

HSS 1042 is a database for user information and stores subscription dataregarding MS 1002 or UE 1024 for handling calls or data sessions.Networks may contain one HSS 1042 or more if additional resources arerequired. Example data stored by HSS 1042 include, but is not limitedto, user identification, numbering or addressing information, securityinformation, or location information. HSS 1042 may also provide call orsession establishment procedures in both the PS and CS domains.

VLR/MSC Server 1028 provides user location functionality. When MS 1002enters a new network location, it begins a registration procedure. A MSCserver for that location transfers the location information to the VLRfor the area. A VLR and MSC server may be located in the same computingenvironment, as is shown by VLR/MSC server 1028, or alternatively may belocated in separate computing environments. A VLR may contain, but isnot limited to, user information such as the IMSI, the Temporary MobileStation Identity (TMSI), the Local Mobile Station Identity (LMSI), thelast known location of the mobile station, or the SGSN where the mobilestation was previously registered. The MSC server may containinformation such as, but not limited to, procedures for MS 1002registration or procedures for handover of MS 1002 to a differentsection of core network 1010. GMSC server 1030 may serve as a connectionto alternate GMSC servers for other MSs in larger networks.

EIR 1044 is a logical element which may store the IMEI for MS 1002. Userequipment may be classified as either “white listed” or “black listed”depending on its status in the network. If MS 1002 is stolen and put touse by an unauthorized user, it may be registered as “black listed” inEIR 1044, preventing its use on the network. A MME 1046 is a controlnode which may track MS 1002 or UE 1024 if the devices are idle.Additional functionality may include the ability of MME 1046 to contactidle MS 1002 or UE 1024 if retransmission of a previous session isrequired.

As described herein, a telecommunications system wherein management andcontrol utilizing a software designed network (SDN) and a simple IP arebased, at least in part, on user equipment, may provide a wirelessmanagement and control framework that enables common wireless managementand control, such as mobility management, radio resource management,QoS, load balancing, etc., across many wireless technologies, e.g. LTE,Wi-Fi, and future 5G access technologies; decoupling the mobilitycontrol from data planes to let them evolve and scale independently;reducing network state maintained in the network based on user equipmenttypes to reduce network cost and allow massive scale; shortening cycletime and improving network upgradability; flexibility in creatingend-to-end services based on types of user equipment and applications,thus improve customer experience; or improving user equipment powerefficiency and battery life—especially for simple M2M devices—throughenhanced wireless management.

While examples of a telecommunications system in which carrier IPpeering methods may be processed and managed have been described inconnection with various computing devices/processors, the underlyingconcepts may be applied to any computing device, processor, or systemcapable of facilitating a telecommunications system. The varioustechniques described herein may be implemented in connection withhardware or software or, where appropriate, with a combination of both.Thus, the methods and devices may take the form of program code (i.e.,instructions) embodied in concrete, tangible, storage media having aconcrete, tangible, physical structure. Examples of tangible storagemedia include floppy diskettes, CD-ROMs, DVDs, hard drives, or any othertangible machine-readable storage medium (computer-readable storagemedium). Thus, a computer-readable storage medium is not a signal. Acomputer-readable storage medium is not a transient signal. Further, acomputer-readable storage medium is not a propagating signal. Acomputer-readable storage medium as described herein is an article ofmanufacture. When the program code is loaded into and executed by amachine, such as a computer, the machine becomes an device fortelecommunications. In the case of program code execution onprogrammable computers, the computing device will generally include aprocessor, a storage medium readable by the processor (includingvolatile or nonvolatile memory or storage elements), at least one inputdevice, and at least one output device. The program(s) can beimplemented in assembly or machine language, if desired. The languagecan be a compiled or interpreted language, and may be combined withhardware implementations.

The methods and devices associated with a telecommunications system asdescribed herein also may be practiced via communications embodied inthe form of program code that is transmitted over some transmissionmedium, such as over electrical wiring or cabling, through fiber optics,or via any other form of transmission, wherein, when the program code isreceived and loaded into and executed by a machine, such as an EPROM, agate array, a programmable logic device (PLD), a client computer, or thelike, the machine becomes an device for implementing telecommunicationsas described herein. When implemented on a general-purpose processor,the program code combines with the processor to provide a unique devicethat operates to invoke the functionality of a telecommunicationssystem.

While a telecommunications system has been described in connection withthe various examples of the various figures, it is to be understood thatother similar implementations may be used or modifications and additionsmay be made to the described examples of a telecommunications systemwithout deviating therefrom. For example, one skilled in the art willrecognize that a telecommunications system as described in the instantapplication may apply to any environment, whether wired or wireless, andmay be applied to any number of such devices connected via acommunications network and interacting across the network. Therefore, atelecommunications system as described herein should not be limited toany single example, but rather should be construed in breadth and scopein accordance with the appended claims.

In describing preferred methods, systems, or apparatuses of the subjectmatter of the present disclosure—enabling IP peering in view of carrierENUM—as illustrated in the Figures, specific terminology is employed forthe sake of clarity. The claimed subject matter, however, is notintended to be limited to the specific terminology so selected, and itis to be understood that each specific element includes all technicalequivalents that operate in a similar manner to accomplish a similarpurpose. In addition, the use of the word “or” is generally usedinclusively unless otherwise provided herein.

This written description uses examples to disclose the invention,including the best mode, and also to enable any person skilled in theart to practice the invention, including making and using any devices orsystems and performing any incorporated methods. The patentable scope ofthe invention is defined by the claims, and may include other examplesthat occur to those skilled in the art (e.g., skipping steps, combiningsteps, or adding steps between exemplary methods disclosed herein). Suchother examples are intended to be within the scope of the claims if theyhave structural elements that do not differ from the literal language ofthe claims, or if they include equivalent structural elements withinsubstantial differences from the literal languages of the claims.

What is claimed:
 1. A computer readable storage medium storing computerexecutable instructions that when executed by a computing device causesaid computing device to effectuate operations comprising: receiving aquery from the first network device, the query associated with aconnection of a first device on a first carrier network with a seconddevice on a second carrier network, wherein the query comprisestElephone NUmber Mapping (ENUM) query with an indication of a telephonenumber associated with the second device, wherein the connection is avoice over internet protocol (IP) connection, wherein the second carriernetwork is not trusted by the first carrier network; determining thatthe indication of the telephone number is not of the first carriernetwork; and responsive to determining that the indication of thetelephone number is not of the first carrier network, providing, basedon matching a destination number or number range, a fully qualifieddomain name (FQDN) to an external routing function to route the call toa destination network.
 2. The computer readable storage medium of claim1, wherein the external routing function comprises a breakout gatewaycontrol function (BGCF).
 3. The computer readable storage medium ofclaim 1, wherein the indication of the telephone number comprises anE.164 number.
 4. The computer readable storage medium of claim 1,wherein the operations are executed on a private ENUM database.
 5. Thecomputer readable storage medium of claim 1, wherein the FQDN is anentry in a private domain name system (DNS) server.
 6. A systemcomprising: a first network device; and a second network devicecommunicatively connected with the first network device, the secondnetwork device comprising: a processor; and a memory coupled with theprocessor, the memory comprising executable instructions that whenexecuted by the processor cause the processor to effectuate operationscomprising: detecting an initiation by the first device on a firstcarrier network of a voice over internet protocol (IP) connection with asecond device on a second carrier network, wherein the second carriernetwork is not trusted by the first carrier network; sending a query fora connection information to the first network device, wherein the querycomprises an indication of a telephone number, wherein the first networkdevice comprises a private tElephone NUmber Mapping (ENUM) database; andresponsive to the query, receiving a first fully qualified domain name(FQDN), wherein the first FQDN indicates the indication of the telephonenumber is not of the first carrier network, and wherein the first FQDNindicates an external routing function for routing the indication of atelephone number based on the destination number or number range.
 7. Thesystem of claim 6, wherein the external routing function comprises abreakout gateway control function (BGCF).
 8. The system of claim 6,wherein the operations of the second network device are executed by aserving call session control function.
 9. The system of claim 6, whereinthe destination number comprises a numbering plan area (NPA) or countrycode.
 10. The system of claim 6, wherein the first FQDN is an entry in aprivate domain name system (DNS) server.
 11. The system of claim 6, theoperations further comprising sending a domain name query to a privatedomain name system (DNS) server to resolve the first FQDN.
 12. Thesystem of claim 6, the operations further comprising: sending a domainname query to a private domain name system (DNS) server to resolve thefirst FQDN; and receiving an internet protocol address of the firstFQDN.
 13. The system of claim 6, the operations further comprising:sending a domain name query to a private domain name system (DNS) serverto resolve the first FQDN; receiving an internet protocol address of thefirst FQDN; and based on the internet protocol address, routing thevoice over IP connection to the BGCF.
 14. The system of claim 6, whereinthe first network device comprises a private tElephone NUmber Mapping(ENUM) database.
 15. A system comprising: a first network device; and asecond network device communicatively connected with the first networkdevice, the second network device comprising: a processor; and a memorycoupled with the processor, the memory comprising executableinstructions that when executed by the processor cause the processor toeffectuate operations comprising: receiving a query from the firstnetwork device, the query associated with a connection of a first deviceon a first carrier network with a second device on a second carriernetwork, wherein the query comprises tElephone NUmber Mapping (ENUM)query with an indication of a telephone number associated with thesecond device, wherein the connection is a voice over internet protocol(IP) connection, wherein the second carrier network is not trusted bythe first carrier network; determining that the indication of thetelephone number is not of the first carrier network; and responsive todetermining that the indication of the telephone number is not of thefirst carrier network, providing, based on matching a destination numberor number range, a fully qualified domain name (FQDN) to an externalrouting function to route the call to a destination network.
 16. Thesystem of claim 15, wherein the first network device comprises a servingcall session control function.
 17. The system of claim 15, wherein theoperations are executed on a private ENUM database.
 18. The system ofclaim 15, wherein the external routing function comprises a breakoutgateway control function (BGCF).
 19. The system of claim 15, wherein theindication of the telephone number comprises an E.164 number.
 20. Thesystem of claim 15, wherein the FQDN is an entry in a private domainname system (DNS) server.